Not Applicable
Not Applicable
The following publications, some of which are identified herein using the reference numbers set forth below, are incorporated herein by reference:
1. G. F. Cerofolini, R. Balboni, D. Bisero, F. Corni, S. Frabboni, G. Ottaviani, R. Tonini, R. S. Brusa, A. Zecca, M. Ceschini, G. Giebel, and L. Pavesi, Hydrogen Precipitation in Highly Oversaturated Single-Crystalline Silicon, Phys. Stat. Sol. (a) 150, 539 (1995).
2. M. Bruel, Silicon on Insulator Material Technology, Electron. Lett. 31, 1201 (1995).
3. M. Bruel, Process for the Production of Thin Semiconductor Material Films, U.S. Pat. No. 5,374,564 (filed Sept. 15, 1992, issued Dec. 20, 1994).
4. X. Lu, S. S. K. Iyer, J. Min. Z. Fan, J. B. Liu, P. K. Chu, C. Hu, and N. W. Chueng, Proc. 1966 IEEE Int. SOI Conf. 96CH35937, 48 (1966).
5. Tohru Hara, Takayuki Onda, Yasuo Kakizaki, Sotaro Oshima, Taira Kltamura, Kenji Kajiyama, Tomoaki Yoneda, Kohei Sekine and Morio Inoue, Delaminations of Thin Layers by High Dose Hydrogen Ion Implantation in Silicon, J. Electrochem. Soc. Vol. 143, No. 8, August 1996L166-L168.
6. L. B. Freund, A lower bound on implant density to induce wafer splitting in forming compliant substrate structures, Appl. Phys. Lett. 70 (26), 30 Jun. 1997.
7. Q.-Y. Tong, K. Gutjahr, S. Hopfe, and U. Goesele and T.-H. Lee, Layer splitting process in hydrogen-implanted Si, Ge, SiC, and diamond substrates, Appl. Phys. Lett. 70, (11), 17 Mar. 1997 pp 1390-1392.
8. Robert W. Bower, Yang A. Li and Yong Jian Chin, The Hydrogen Ion Cut Technology Combined With Low Temperature Direct Bonding, Proceedings of SPIE, Vol. 3184, pp 2-4, June 1997.
9. Y. Albert Li and Robert W. Bower, Surface Conditions and Morphology of Hydrogen Ion Cut Low Temperature Bonded Thin Film Layers, Submitted JJAP.
10. Q.-Y. Tong, T.-H. Lee, L.-J. Huang, Y.-L. Chao and U. Goesele, Low Temperature Si Layer Splitting, Proceedings 1977 IEEE International SOI Conference, October 1997 pp 126-127.
11. Aditya Agarwal, T. E. Haynes, V. C. Venezia, D. J. Eaglesham, M. K. Weldon, Y. J. Chabal, and O. W. Holland, Efficient Production of Silicon-on-Insulator Films by Co-implantation of He+ with H+, Proceedings 1977 IEEE International SOI Conference, October 1997 pp 44-45.
12. J. L. Zeigler and J. P. Biersack, The Stopping and Range of Ions in Solids, Trim 95, Pergamon Press (1985) ISBN-0-08-021603-X.
13. A. D. Marwick, G. S. Oehrlein, and M. Wittmer, High hydrogen concentrations produced by segregation into p+ layers in silicon, Appl. Phys. Lett. 59 (2), 8 Jul. 1991, pp 198-200.
14. Robert W. Bower, Louis LeBoeuf and Y. Albert Li, xe2x80x9cTransposed Splitting of Silicon Implanted with Spatially Offset Distributions of Hydrogen and Boronxe2x80x9d. II Nuovo Cimento, Vol. 19 D, N. 12, pp 1871-1873, 1 Jan. 1998.
1. Field of the Invention
This invention pertains generally to introducing atoms into solid materials, and more particularly to forming and selectively introducing acceptor centers into a solid material and introducing atoms into the solid material wherein the location of the major concentration of the acceptor centers is offset spatially from the introduced atoms in the solid material.
2. Description of the Background Art
In recent years, it has been observed that atoms introduced into solid materials can result in a thin layer of the material being expunged from the solid material when a stiffener is attached to the solid material and a suitable stress is created to cause the layer crack and break off [1,2,3]. It has been found that the thickness of the expunged layer is very near that of the mean penetration depth of the introduced ions or the nearby damage peak created by the introduced ions, when the introduced ions are ion implanted into the solid material. It has also been observed that atoms that act as acceptor centers in semiconductor materials tend to attract and condense injected ions near the acceptor centers location in the material.
There has also been considerable interest in high dose hydrogen ion implantation into silicon. A recent review article describes a wealth of basic physical theory and experiments related to hydrogen implanted silicon [1]. Bruel first described the Smart Cut(copyright) technique that leads to silicon-on-insulator, SOI, material for use in silicon microcircuits [2,3]. Since that time a number of authors have described and have proposed theories to quantify the hydrogen bubble generation and crack phenomena that in combination with direct bonding leads to SOI formation [4,5,6]. Recent publications have described variations on Bruel""s work. Tong et al. have described layer splitting with ion implanted hydrogen in Ge, SiC, GaAs and diamond [7]. Bower et al. have demonstrated that low temperature bonding may be used with hydrogen ion implantation to produce SOI with a bonding temperature of 200xc2x0 C. and a split temperature of 400xc2x0 C. [8,9]. Tong et al. have shown that boron and hydrogen when implanted to the same projected range allow optically observable surface blisters to be produced with heat treatments of 200xc2x0 C. for approximately 100 minutes [10]. Agarwal et al. have demonstrated that the hydrogen ion dose may be reduced from 5xc3x971016/cm2 to 1xc3x971016/cm2 when silicon is also implanted with Helium also at a dose of 1xc3x971016/cm2 [11].
The present invention generally comprises the steps of forming and selectively introducing acceptor centers into a solid material and then introducing atoms into the solid material wherein the location of the major concentration of the acceptor centers is offset spatially from the introduced atoms in the solid material. When these steps are carried out so that the atoms introduced into the solid material can be transported in the material, then the introduced atoms may be diffused or drifted to the location of the acceptor centers that have been selectively placed in the material. The introduced atoms will then condense in the region of the acceptor centers. As a result, then any expunged layer that forms as a result of the atoms being introduced into the solid material will follow the contour of the location of the acceptor centers, and will thus be transposed from the initial location of the atoms introduced into the solid material.
Therefore, this invention allows an expunged layer to be formed and transferred to a stiffener that is embedded in the material independent of the location of the introduced atoms.
An object of the invention is to expunge a layer of a solid material along a contour line defined by acceptor centers formed in the material.
Another object of the invention is to transpose the initial location of atoms introduced into the solid material to the location of the acceptor centers prior to expunging a layer of the solid material using the atoms.
Another object of the invention is to ion cut a material in a region spaced apart from the location where atoms are introduced into the material.
Further objects and advantages of the invention will be brought out in the following portions of the specification, wherein the detailed description is for the purpose of fully disclosing preferred embodiments of the invention without placing limitations thereon.